#include "spi.h"
 
void SPI2_Init(void)
{
  GPIO_InitTypeDef GPIO_InitStructure;
  SPI_InitTypeDef  SPI_InitStructure;
 

//  /* Enable SCK, MOSI and MISO GPIO clocks */
  RCC_AHBPeriphClockCmd(RCC_AHBPeriph_GPIOC|RCC_AHBPeriph_GPIOB, ENABLE);
  
  GPIO_InitStructure.GPIO_Mode = GPIO_Mode_OUT;//复用
  GPIO_InitStructure.GPIO_OType = GPIO_OType_PP;//推挽输出
  GPIO_InitStructure.GPIO_PuPd  = GPIO_PuPd_UP;//上啦
  GPIO_InitStructure.GPIO_Speed = GPIO_Speed_10MHz;//时钟速率
  GPIO_InitStructure.GPIO_Pin = GPIO_Pin_6;
  GPIO_Init(GPIOC, &GPIO_InitStructure);
  GPIO_SetBits(GPIOC, GPIO_Pin_6);  
    
 
  GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF;//复用
  GPIO_InitStructure.GPIO_OType = GPIO_OType_PP;//推挽输出
 // GPIO_InitStructure.GPIO_PuPd  = GPIO_PuPd_UP;//上啦
  GPIO_InitStructure.GPIO_Speed = GPIO_Speed_10MHz;//时钟速率
  GPIO_InitStructure.GPIO_Pin =  GPIO_Pin_13 | GPIO_Pin_14 | GPIO_Pin_15;
  GPIO_Init(GPIOB, &GPIO_InitStructure);
  GPIO_SetBits(GPIOB, GPIO_Pin_13 | GPIO_Pin_14 | GPIO_Pin_15);  

  GPIO_PinAFConfig(GPIOB, GPIO_PinSource13, GPIO_AF_SPI2);
  GPIO_PinAFConfig(GPIOB, GPIO_PinSource14, GPIO_AF_SPI2);
  GPIO_PinAFConfig(GPIOB, GPIO_PinSource15, GPIO_AF_SPI2);
 // GPIO_PinAFConfig(GPIOC, GPIO_PinSource7, GPIO_AF_SPI2);//GPIO_PinSource7
  /* SPI configuration -------------------------------------------------------*/
//  SPI_I2S_DeInit(SPI2);
   /* Enable the SPI periph */
  RCC_APB1PeriphClockCmd(RCC_APB1Periph_SPI2, ENABLE);
  SPI_InitStructure.SPI_Direction = SPI_Direction_2Lines_FullDuplex;//SPI设置为双线双向全双工
  SPI_InitStructure.SPI_Mode = SPI_Mode_Master;		//设置SPI工作模式:设置为主spi
  SPI_InitStructure.SPI_DataSize = SPI_DataSize_8b;
  SPI_InitStructure.SPI_CPOL = SPI_CPOL_Low;
  SPI_InitStructure.SPI_CPHA = SPI_CPHA_1Edge;
  SPI_InitStructure.SPI_NSS = SPI_NSS_Soft;
  SPI_InitStructure.SPI_BaudRatePrescaler = SPI_BaudRatePrescaler_8;
  SPI_InitStructure.SPI_FirstBit = SPI_FirstBit_MSB;
  SPI_InitStructure.SPI_CRCPolynomial = 7;
  SPI_Init(SPI2, &SPI_InitStructure);
  SPI_Cmd(SPI2, ENABLE); //使能SPI外设
//  SPI2_SetSpeed(1);
//  SPI2_ReadWrite(0xff);//启动传输	
}
//SPI2速度设置函数
//SpeedSet:0~7
//SPI速度=fAPB1/2^(SpeedSet+1)
//APB1时钟一般为36Mhz
void SPI2_SetSpeed(u8 SpeedSet)
{
	SpeedSet&=0X07;			//限制范围
	SPI2->CR1&=0XFFC7; 
	SPI2->CR1|=SpeedSet<<3;	//设置SPI2速度  
	SPI2->CR1|=1<<6; 		//SPI设备使能	  
} 
//SPI 速度设置函数
//SpeedSet:
//SPI_BaudRatePrescaler_2   2分频   (SPI 36M@sys 72M)
//SPI_BaudRatePrescaler_8   8分频   (SPI 9M@sys 72M)
//SPI_BaudRatePrescaler_16  16分频  (SPI 4.5M@sys 72M)
//SPI_BaudRatePrescaler_256 256分频 (SPI 281.25K@sys 72M)
  
//void SPI2_SetSpeed(u8 SpeedSet)
//{
//	SPI_InitTypeDef  SPI_InitStructure;
//	
//	SPI_InitStructure.SPI_BaudRatePrescaler = SpeedSet ;
//  SPI_Init(SPI2, &SPI_InitStructure);
//	SPI_Cmd(SPI2,ENABLE);
//} 
//SPI2 读写一个字节
//TxData:要写入的字节
//返回值:读取到的字节
u8 SPI2_ReadWriteByte(u8 TxData)
{		
	u16 retry=0;				 
	while((SPI2->SR&1<<1)==0)		//等待发送区空	
	{
		retry++;
		if(retry>=0XFFFE)return 0; 	//超时退出
	}			  
	SPI2->DR=TxData;	 	  		//发送一个byte 
	retry=0;
	while((SPI2->SR&1<<0)==0) 		//等待接收完一个byte  
	{
		retry++;
		if(retry>=0XFFFE)return 0;	//超时退出
	}	  						    
	return SPI2->DR;          		//返回收到的数据				    
}